In the early 1970's network broadcasters saw a need for their local television stations to have an automated master control system that worked hand in hand with a traffic and sales system. The initial goal was to create sales orders and a schedule that could then be formatted into a file that could be loaded into a computer system. This computer would then control the systems used in the master control operation. Finally the completed log with accurately logged air times and log discrepancies would be returned to the sales system allowing for an automated billing to clients. That traffic and sales system originally ran on a mainframe computer system. The automation system ran on a Digital Equipment Corporation (DEC) PDP11 computer. These two systems would later become the Integrated Broadcast System (IBS) and Real Time (RT) respectively.
Network broadcasters such as CBS also own and operate many local affiliate stations throughout the country. Each of these local stations broadcasts the network master schedule. The master schedule is a detailed down to the second account of that day's programming. Programming may include television programs and advertisement spots herein after referred to as programs and spots.
Today, consumers may obtain television service from one of many different alternatives. In addition to over-the-air (OTA) reception of locally broadcast television signals, consumers may receive television programming through service providers such as cable television service providers, satellite television service providers, and television over telephone line service providers. A network feeds its broadcast schedule and content to each of its local stations (e.g., affiliates). The local stations must then insert the various spots into the schedule along with the programs and distribute a broadcast signal to each of the television service providers as well as broadcast the signal over-the-air.
The same spots are inserted into the broadcast signal before it is disseminated to the various television service providers. If one of the service providers purchases an advertising spot, it will air regardless of the television service provider. Thus, a cable operator may air a spot intended to attract new customers. The spot will air to every consumer regardless of their television service provider. This is fine for all but the cable operators own subscribers since they already subscribe. The spot for the cable operator's own subscribers is essentially wasted since they are already subscribed to the service. If the cable operator has a market share of 35% for that local market, the spot is only 65% effective. There are currently no means for providing a different spot to the cable operators own subscribers.